The cyclization of arylalkynes under selenobromination conditions, combined with an acid-induced 3,2-aryl shift, was elaborated as a general synthetic pathway for the preparation of polyhydroxy-2- and -3-arylbenzo[b]selenophenes from the same starting materials. The redox properties, free-radical-scavenging ability, and cytotoxicity against malignant cell lines (MCF-7, MDA-MB-231, HepG2, and 4T1) of the synthesized compounds were explored, and the obtained results were used to consider the structure-activity relationships (SARs) in these compounds. Consequently, the structural features that were responsible for the highly potent peroxyl-radical-scavenging activity were established.

The cyclization of substituted diaryl(hetaryl)alkynes with in‐situ‐prepared SeBr4 has been achieved. The use of an alkene additive as a bromine scavenger gives simple access to functionalized benzo[b]selenophene and selenophenothiophene derivatives from commercially available or easily accessible starting materials. The reactions can be performed in air without the use of moisture‐sensitive reagents, dry solvents, or an inert atmosphere. Mechanistic studies confirmed a regioselective anti 1,2‐addition in the selenobromination step, and a subsequent electrophilic substitution in the aromatic ring to complete the cyclization.

A novel method for the cyclization of phenylalkyne derivatives (I) and (III) by selenobromination is developed to produce a variety of 3‐bromobenzo[b]selenophenes.

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An investigation of regularities of surface‐tension alterations in the aqueous solutions of lignosulfonate and aluminum‐containing organosilicon oligomer (olygoheterosiloxanolates) reaction mixtures revealed that modification with oligomers can be used for the regulation of the surface activity of lignosulfonates. High surface activity not only in acidic, but also in neutral and alkali media, is achieved using oligomers which consist of ethylsesquioxane and diethylsiloxane links. In this case, increasing hydrophobicity compensates the negative effects (increase of solubility and the Coulomb repulsion) of ionization of lignosulfonate acidic groups. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1013–1020, 2001

Resveratrol is a natural (poly)phenol primarily found in plants protecting them against pathogens, as well as harmful effects of physical and chemical agents. In higher eukaryotic cells and organisms, this compound displays a remarkable range of biological activities, such as anti-oxidant, anti-inflammatory, anti-cancer, anti-aging, cardio- and neuro-protective properties. Here, biological activities of synthetic selenium-containing derivatives of resveratrol—benzo[b]selenophenes—have been studied in lower eukaryotes Saccharomyces cerevisiae. Their toxicity, as well as DNA damaging and reactive oxygen species (ROS) inducing potencies, manifested through their ability to act as redox active anti-microbial agents, have been examined. We show that some benzo[b]selenophenes can kill yeast cells and that the killing effects are not mediated by DNA damage types that can be detected as DNA double-strand breaks. These benzo[b]selenophenes could potentially be used as anti-fungal agents, although their concentrations relevant to application in humans need to be further evaluated. In addition, most of the studied benzo[b]selenophenes display redox-modulating/anti-oxidant activity (comparable or even higher than that of resveratrol or Trolox) causing a decrease in the intracellular ROS levels in yeast cells. Therefore, after careful re-evaluation in other biological systems these observations might be transferred to humans, where resveratrol-inspired benzo[b]selenophenes could be used as supra-anti-oxidant supplements.